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<TITLE>80386 Programmer's Reference Manual -- Section 14.4</TITLE>
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Chapter 14 -- 80386 Real-Address Mode</A><BR>
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<H1>14.4  Entering and Leaving Real-Address Mode</H1>
Real-address mode is in effect after a signal on the RESET pin. Even if the
system is going to be used in protected mode, the start-up program will
execute in real-address mode temporarily while initializing for protected
mode.

<H2>14.4.1  Switching to Protected Mode</H2>
The only way to leave real-address mode is to switch to protected mode. The
processor enters protected mode when a 
<A HREF="MOVRS.htm">MOV</A> to CR0 instruction sets the PE
(protection enable) bit in CR0. (For compatibility with the 80286, the LMSW
instruction may also be used to set the PE bit.)
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Refer to 
<A HREF="c10.htm">Chapter 10</A>
   "Initialization" for other aspects of switching to
protected mode.
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Chapter 14 -- 80386 Real-Address Mode</A><BR>
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<B>next:</B> <A HREF="s14_05.htm">14.5  Switching Back to Real-Address Mode</A>
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